优化了平衡，尤其对于向后倾倒的几种极限情况进行优化

Shibo-main-TOMMY/lib/ArduinoJson/extras/tests/JsonObject/clear.cpp

@@ -0,0 +1,25 @@
+// ArduinoJson - https://arduinojson.org
+// Copyright © 2014-2023, Benoit BLANCHON
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonObject::clear()") {
+  SECTION("No-op on null JsonObject") {
+    JsonObject obj;
+    obj.clear();
+    REQUIRE(obj.isNull() == true);
+    REQUIRE(obj.size() == 0);
+  }
+
+  SECTION("Removes all elements") {
+    StaticJsonDocument<64> doc;
+    JsonObject obj = doc.to<JsonObject>();
+    obj["hello"] = 1;
+    obj["world"] = 2;
+    obj.clear();
+    REQUIRE(obj.size() == 0);
+    REQUIRE(obj.isNull() == false);
+  }
+}